1. Field of the Invention
The present invention relates to techniques for preventing laser damage to optical systems, and more specifically, it relates to a pulse bandwidth analysis interlock.
2. Description of Related Art
Modern laser systems often require broad bandwidth for short pulse applications, driving high energy density physics experiments, or suppression of nonlinear effects in optical materials. Laser architectures designed to deliver this broad bandwidth can often be damaged if the laser bandwidth is too low. The use of bandwidth is generally done to suppress nonlinear optical effects that are bandwidth dependent, to enable smoothing by spectral dispersion or to enable a pulse to be stretched in time for amplification. Often a system is built to rely on this bandwidth since the fluence may be safely increased in fiber or bulk systems with the presence of bandwidth or a stretched pulse. However, once the system is designed this way, catastrophic damage to high value systems can occur if even a single pulse is generated without bandwidth. A spectral interlock is desired that is able to evaluate an individual pulse from a pulse train to ensure it meets minimum bandwidth requirements and, if not, remove that pulse from the pulse train. It is further desirable that the system is flexible enough to allow use over a broad range of bandwidths encountered in the marketplace. It must run at a broad range of repetition rates, from shot-on-demand to e.g., 5 MHz.